<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>

<body>
    <script>
        var arr = [3, 6, 12, 9, 32, 1, 23];
        for (j = 0; j < arr.length - 1; j++) {
            var minIndex = j;
            for (i = 1+j; i < arr.length; i++) {
                if (arr[i] < arr[minIndex]) {
                    minIndex = i;
                }
            }
            var temp = arr[j];
            arr[j] = arr[minIndex];
            arr[minIndex] = temp;
        }
        console.log(arr);
    </script>
</body>

</html>